Causes of cystic fibrosis?

2009-01-07 08:05:15

2009-01-07 08:05:15

It is caused by either both parents being CF carriers or one
parent having CF and the other being a carrier and then the
children getting it genetically. However the parents do not have to
have CF to be a carrier as it is a recessive trait (if they have
one CF gene and one non-CF gene, they will not have CF but there is
a chance their children may if the other parent is also a CF
carrier). Cystic fibrosis is a genetic disease. That means people
inherit it from their parents through genes (or DNA), which also
determine a lot of other characteristics including height, hair
color and eye color. Genes, found in the nucleus of all the body's
cells, control cell function by serving as the blueprint for the
production of proteins. The defective gene that is responsible for
causing cystic fibrosis is on chromosome 7. To have cystic
fibrosis, a person must inherit two copies of the defective CF
gene—one copy from each parent. If both parents are carriers of the
CF gene (i.e., they each have one copy of the defective gene),
their child will have a 25% chance of inheriting both defective
copies and having cystic fibrosis, a 50% chance of inheriting one
defective copy and being a carrier, and a 25% chance of not having
CF or carrying the gene. Approximately 30,000 people in the United
States have cystic fibrosis. An additional ten million more—or
about one in every 31 Americans—are carriers of the defective CF
gene, but do not have the disease. The disease is most common in
Caucasians, but it can affect all races. The severity of cystic
fibrosis symptoms is different from person to person. The most
common symptoms are: Very salty-tasting skin

Persistent coughing, at times with phlegmFrequent lung infections,
like pneumonia or bronchitisWheezing or shortness of breathPoor
growth/weight gain in spite of a good appetiteFrequent greasy,
bulky stools or difficulty in bowel movementsSmall, fleshy growths
in the nose called nasal polypsSometimes people are told that they
have asthma or chronic bronchitis when they really have cystic
fibrosis. New research shows that the severity of CF symptoms is
partly based on the types of CF gene mutations (defects).
Scientists have found more than 1,500 different mutations of the CF
gene.